static int ogg_read_page(AVFormatContext *s, int *str) { AVIOContext *bc = s->pb; struct ogg *ogg = s->priv_data; struct ogg_stream *os; int ret, i = 0; int flags, nsegs; uint64_t gp; uint32_t serial; int size, idx; uint8_t sync[4]; int sp = 0; ret = avio_read (bc, sync, 4); if (ret < 4) return ret < 0 ? ret : AVERROR_EOF; do{ int c; if (sync[sp & 3] == 'O' && sync[(sp + 1) & 3] == 'g' && sync[(sp + 2) & 3] == 'g' && sync[(sp + 3) & 3] == 'S') break; c = avio_r8(bc); if (url_feof(bc)) return AVERROR_EOF; sync[sp++ & 3] = c; }while (i++ < MAX_PAGE_SIZE); if (i >= MAX_PAGE_SIZE){ av_log (s, AV_LOG_INFO, "ogg, can't find sync word\n"); return AVERROR_INVALIDDATA; } if (avio_r8(bc) != 0) /* version */ return AVERROR_INVALIDDATA; flags = avio_r8(bc); gp = avio_rl64 (bc); serial = avio_rl32 (bc); avio_skip(bc, 8); /* seq, crc */ nsegs = avio_r8(bc); idx = ogg_find_stream (ogg, serial); if (idx < 0){ if (ogg->headers) { int n; for (n = 0; n < ogg->nstreams; n++) { av_freep(&ogg->streams[n].buf); av_freep(&ogg->streams[n].private); } ogg->curidx = -1; ogg->nstreams = 0; idx = ogg_new_stream(s, serial, 0); } else {
static int skeleton_header(AVFormatContext *s, int idx) { struct ogg *ogg = s->priv_data; struct ogg_stream *os = ogg->streams + idx; AVStream *st = s->streams[idx]; uint8_t *buf = os->buf + os->pstart; int version_major, version_minor; int64_t start_num, start_den; uint64_t start_granule; int target_idx, start_time; strcpy(st->codec->codec_name, "skeleton"); st->codec->codec_type = AVMEDIA_TYPE_DATA; if (os->psize < 8) return -1; if (!strncmp(buf, "fishead", 8)) { if (os->psize < 64) return -1; version_major = AV_RL16(buf+8); version_minor = AV_RL16(buf+10); if (version_major != 3) { av_log(s, AV_LOG_WARNING, "Unknown skeleton version %d.%d\n", version_major, version_minor); return -1; } // This is the overall start time. We use it for the start time of // of the skeleton stream since if left unset lavf assumes 0, // which we don't want since skeleton is timeless // FIXME: the real meaning of this field is "start playback at // this time which can be in the middle of a packet start_num = AV_RL64(buf+12); start_den = AV_RL64(buf+20); if (start_den) { int base_den; av_reduce(&start_time, &base_den, start_num, start_den, INT_MAX); avpriv_set_pts_info(st, 64, 1, base_den); os->lastpts = st->start_time = start_time; } } else if (!strncmp(buf, "fisbone", 8)) { if (os->psize < 52) return -1; target_idx = ogg_find_stream(ogg, AV_RL32(buf+12)); start_granule = AV_RL64(buf+36); if (os->start_granule != OGG_NOGRANULE_VALUE) { av_log_missing_feature(s, "multiple fisbone for the same stream", 0); return 1; } if (target_idx >= 0 && start_granule != OGG_NOGRANULE_VALUE) { os->start_granule = start_granule; } } return 1; }